Bttrorlar



W. TIERNEY.

BUBGLAR ALARM.

'APPLICATlON FILED MAR. 21. 1919.

Patented June 17, 1919.

NIED STATES PA i1 rib.

BURGLAR-ALARM.

Specification of Letters Patent.

Patented June 17, 1919.

Application filed March 21, 1919. Serial No. 283,976.

To all whom it may concern:

Be it known that I, WILLIAM TIERNEY, a citizen of, the United States,residing at Seattle, in the county of King and State of Washington, haveinvented certain new and useful Improvements in Burglar-Alarms, of whichthe following is a specification.

This invention relates to burglar alarms.

The primary object of the invention is to provide a device adapted to belocated adjacent a door or a window, so that when the latter is opened,mechanism will be released and an alarm sounded.

The invention also comprehends improve ments in the details ofconstruction and arrangement of parts which will be hereinafterdescribed and particularly pointed out in the claim.

In the drawing Figure 1 is a perspective view illustrating theapplication of the invention. a

Fig. 2 is a cross section on the line 2-2 of Fig. 1.

The invention is shown as applied to a door, but it is to be understoodthat it may be also applied to a window.

1 indicates a door jam'b, and 2 a door. To the door jamb is secured theimproved device which will now be described.

3, represents a base fastened to the jamb and provided with a pair ofoutstanding lugs 4:, formed with alined openings 5, and intermediate thelugs is an L-shaped slot 6.

Mounted to reciprocate through the openings 5, is a rod 7, which ispointed at one end to form a firing pin 8, which normally projectsslightly beyond the upper lug 4:, and at the lower end of the rod is ahandle 9. Extending from the rod is a pin 10, which operates in theL-shape slot 6, and between the pin and the lower lug 4, and encirclingthe rod is a coil spring 11, the tension of which tends to force thefiring pin beyond the upper lug 4. The rod 7 is provided with a recess12, and cooperating therewith is a trigger 13. The trigger comprises anL-shape lever pivoted at 14, to the underside of the upper lug 4.Extending from one leg 15, of the L-shape lever is a lug 16, designed,when the device is set to engage in the recess 12, in the rod 7 Theother leg 17, of the L-slrape lever extends outwardly from the lug, andto it may be attached-a cord to release the device.

Extending from the upper end of the base 2, is a lug 18, formed with acartridge seat 19, in alinement with the firing pin 8.

In use the device is secured on a door jamb so that the leg 15 of thetrigger will be in the path of movement of the door 2, then by pullingdown the rod 7 and compressing the spring until the recess 12, is inposition adjacent the trigger, the latter is rocked on its pivot and isengaged in the recess 12, and the parts are locked in operativerelation. If the door is opened it strikes the leg 15 of the trigger,and the lug 16, is disengaged from the recess and the spring quicklyforces the rod beyond the upper lug 4, and the firing pin engages acartridge 21, supported in the seat 19, and an audible signal isproduced. Of course in lieu of the door operating the trigger,thedlatter may be tripped by pulling the cor If it be desired to lockthe rod in set position and at the same time prevent the triggerreleasing it, the rod is pulled down until the pin 10, is opposite theshort end of the L-shape slot 6, and is then turned. By this means therod may be held and the door opened without firing the cartridge.

What I claim is: p

A burglar alarm of the character described, comprising a substantiallyvertical base to be secured to the door jamb, said base being providedbetween its ends with an L-shaped slot, upper and lower horizontal lugscarried by the base and arranged albove and below the L-shaped slot, arod mounted to slide within openings in the lugs and provided at itslower end with an element to turn it and having its upper end pointed,said rod being provided near its upper pointed end with a transverserecess providing a shoulder, a horizontal pin rigidly secured to the rodand operating within the L-shaped slot, a compressible coil springsurrounding the rod and engaging the lower lug and the pin to move therod upwardly, a trigger lever pivoted to the upper lug and having anextension to enter the recess of the rod to engage the shoulder, saidtrigger lever extending in the path of travel of the door, and acartridge holding lug carried by the base and arranged above the upperlug.

In testimony whereof I affix my signature.

WILLIAM TIERNEY.

Copies of this patent may be obtained for five cents each, by addressingthe Commissioner of Patents,

Washington, D. 0.

